Revolver-type pistol for firing shotgun cartridges



REVOLVER-TYPE PISTOL FOR FIRING SHOTGUN CARTRIDGES Filed Dec. 1, 1966 G.H. F'REED Oct. 29, 1968 2 Sheets-Sheet 1 b fin mm Oct. 29, 1968 G. H.FREED 3,407,526

REVOLVER-TYPE PISTOL FOR FIRING SHOTGUN CARTRIDGES Filed Dec. 1, 1966 2Sheets-Sheet 2 x S w Ti E.

IN VENTOR.

650/?65 A4 FQEED United States ABSTRACT OF THE DISCLOSURE Single ordouble-action revolver-type pistol for firing shotgun cartridgescontaining all types of loads including multiple large ball loads (i.e.,ball diameter approximates breech-bore diameter of barrel); pistollength barrel has plurality of immediately adjacent smooth-bored barrelbore portions of sequentially reduced diameter towards muzzle end,thereby defining one or preferably more abrupt chokes within the barrel;that shortdength bore portion (i.e., length less than that of the loadto be fired) which extends between the last such choke and the muzzleend of the barrel has rifling therein; smooth-bored bar rel portionadjacent breech end extends major portion of barrel length; remainingsmooth-bored barrel portions have respective lengths at least equal tobreech end barrel bore diameter; button release of cylinder stop formanually rotating cylinder; and indicia on cylinder adjacent eachcartridge receiving chamber distinguishing type of load therein fromdifferent type loads in other chambers.

Specification This application is a continuation-impart of my copendingapplication Ser. No. 534,844, filed Mar. 16, 1966, now abandoned.

This invention relates to firearms and more particularly to those havingspecial purpose applications.

In police and military work, for example, it has heretofore beennecessary that a variety of weapons, such as pistols, shotguns, rifles,flare guns, tear gas guns, etc. be available for use by an oflicer inlocating, approaching, and apprehending criminals or the like, and forriot control and other purposes. The provision of such multiple firearmsis expensive and, of course, the equipping of each individual oflicerwith such multiplicity of Weapons is impractical for obvious reasons.Thus, such variety of weapons can be made available only to oflicers whoare also furnished with motor vehicles in which the weapons are carried.

The present invention provides a single firearm, in pistol form forconvenient carrying and shooting, which is capable of selective firingof a variety of loads as would ordinarily be necessary or desirable insuch police or military work. Of course, the firearm provided by theinvention will also be found useful to hunters in locating and killinggame. Thus, when carrying the single Weapon of the present invention,the scope of available techniques which the user may employ in hunting,criminal apprehension, crowd control and other circumstances is greatlyenhanced without the need for carrying a multipility of special purposeweapons.

In a related aspect, the invention provides particular features in a:gun barrel rendering it capable of firing buckshot and exceptionallylarge sized single and multiple ball loads with safety, high accuracy,and optimum spread pattern, even though the barrel has no heavier thanaverage weight and is no longer than is conventional for pistols. Forexample, in its preferred embodiment the pistol receives size .410 gaugeshotgun-type cartridges up to 3 long, and its barrel is adapted for safeand accurate firing of up to a five-ball multiple load where thediameter of each of the five balls is the maximum which the cartridgecasing will accept, i.e. up to .410" or slightly less. Further, whereasa conventional shotgun has a spread pattern such that, depending uponwhether its barrel is choked or not, it is capable of placing from35-40% (no choke) to about 70% (full choke) of its fired multiple shotload within a 30" diameter target at a range of 40 yards, of multipleshot loads (even the referred to large ball loads) fired from a pistolin accordance with the preferred embodiment of the present inventionwill be placed within a 20" diameter target at the same range. Moreover,muzzle velocity for given loads is thought not to be significantlyreduced, so that the pistol may be said to have virtually the same rangeas conventional shotguns and pistols.

Thus, the advantages to law enforcement oflicers, troops in wartime, andsimilar personnel having a pistol-type firearm, capable of firingmultiple large-ball loads as well as conventional buckshot with the samerange and better accuracy than a conventional shotgun or pistol, aremanifest. For example, even comparing the results with those of asemi-automatic or automatic rifle, the chance of bringing down a swiftlymoving or darting target with a single shot of five heavy slugs fired ina spread pattern, any one of which is capable of a kill, is far betterthan that afforded by five shots even rapidly fired in succession withwhat must be more careful aim.

With regard to the prior art, applicant is aware of pistoltype firearmscapable of firing buckshot loads (see, for example, Le Mat US. Patent15,925); pistol-type gas guns (see, for example, Manville US. Patent2,151,521); the so-called paradox bore standard-size shotguns; andconventionally choked shotguns and long-taper choke shotguns. However,none of these known guns achieve the results afforded by the presentinvention. For example, an up-to-date authoritative source states withregard to chokes in firearms that, Spherical balls (fired from suchweapons) must be no larger than the smallest diameter of any choke inwhich they might conceivably be fired. In contrast, the preferredembodiment of the present invention safely fires single and multiplespherical ball loads, where each ball diameter approximates .410",through a final choke barrel diameter of .350", i.e., .060" constrictionas compared with the conventional maximum of .040" constriction infull-choked guns.

Briefly, the invention in its preferred embodiment provides a revolvertype pistol incorporating both single action and double action movementof its firing mechanism and 'having a rotatable cylinder for containinga plurality of .410" gauge shotgun type cartridges, a means for manuallyreleasing the cylinder for manual rotation to selectively index any ofits cartridge chambers into alignment with the barrel independently ofany movement of its firing mechanism, and a particular type of bore ofits barrel which adapts the pistol to fire any of a variety of types ofcartridge loads. Thus, the individual cartridges which the pistol iscapable of firing may be loaded either as blanks for celebration andother sport uses, as a flare, or with tear gas, bird shot, buck shot,rifled slug, or multiple-ball loads, and the pistol may be loaded with avariety of such cartridge loads for firing in any selected order. Acylinder-stop release button is employed to re lease the cylinder formanual rotation when the cylinder is in its position ready for firing.Indicia appears on the pistol cylinder to identify at the time ofselection the type of cartridge contained in any particular cartridgechamber, or to avoid mistake when loading the pistol as to the sequenceof firing where it is anticipated that rapid sequence of firing will berequired. It has been found that all of the several mentioned types ofloads may be safely and accurately fired through a barrel which is 3smooth-bored over the major portion of its length from its breech end,and has multiple stepdown parallel chokes as described over theremainder of its length towards its muzzle end, and is rifled along itsconstricted length immediately adjacent its muzzle end.

Thus, in night time police or military work for example, after properlyloading the pistol an ofiicer may first fire a flare type shell tomomentarily light his target, and then select either tear gas, rifledslug, multi-ball or other buck shot load to fire on his target under theparticular circumstances which he observes.

It is believed that the diameter of the barrel can be larger or smallerthan .410", provided the features of the invention are incorporatedtherein, and that cartridges having either conventional or especiallyadapted gauge, or length, or load may be used in conjunction with theinvention.

These and other objects, features and advantages of the invention willbecome apparent from the following detailed description of the inventionwhen taken together with the accompanying drawings in which:

FIGURE 1 is a side view of a pistol incorporating the invention, itshandle grip plates being removed and its barrel being shown incross-section;

FIGURE 2 is an enlarged and fragmentary cross-sectional showing of thefiring action mechanism of the same istol;

p FIGURE 3 is a similarly enlarged sectional view of the same pistol, asseen from lines 3-3 in FIGURE 2;

FIGURE 4 is a sectional view of the pistol barrel as seen from lines 4-4in FIGURE 1;

FIGURE 5 is a perspective showing approximately to the scale of FIGURE 2of only the cylinder-stop element and its associated spring and releasebutton, as incorporated in the same pistol;

FIGURES 6 to 8 are cross-sectional showings to the scale of FIGURE 1 ofcartridges which may be fired using the pistol, to illustrate only threeof the several types of loads which such cartridges may contain;

FIGURE 9 is a fragmentary cross-sectional view, to an enlarged scale, ofonly the barrel portion of a firearm incorporating a preferred modifiedform of the invention; and

FIGURE 10 is an 9 of a pistol barrel incorporating a preferred form ofthe invention.

Referring first to FIGURE 1, a revolver type p stol incorporating theinvention is generally indicated by reference numeral 10. The pistol hasa frame 11 to which is attached a barrel 12, and on which is mounted arotatable cartridge receiving cylinder 13 and the elements whichtogether provide its firing action mechanism. As shown in FIGURE 2, thefiring action mechanism is generally indicated by reference numeral 14and is of a conventional Colt type comprising a hammer 15, a trigger 16,a hand element 17, a main spring 18, a rebound lever 19, and a cylinderstop lever 20. Although a Colt firing action mechanism is illustrated,it will be understood that other firing action mechanisms may beemployed.

Although a mechanism capable of only single-action firing might be used,the described mechanism 14 is capable of both single-action anddouble-action firing as is desirable for affording maximum utility ofthe firearm. That is, the hammer 15, which is pivotally mounted on theframe 11 by a hammer pin 21, includes both a singleaction sear 23 whichin the illustrated released position of the hammer and trigger engagesthe underside of the trigger sear 24, and a double-action sear 25 whichis pivotally mounted on hammer by a strut pin 26 and is biased outwardlyby a strut spring 27 against the stop 28 of the hammer 15. Thus, uponmanually moving the hammer 15 in the direction of arrow A and againstthe bias of mainspring 18 from its released position shown in FIGURES 1and 2, to its position in which its singleaction sear 23 becomesinterlocked with the trigger sear enlarged showing similar to FIGUREmodification of the 24, the mechanism is cocked for single-actionfiring; whereas upon finger movement of the trigger 16 in the directionof arrow B the trigger sear 24 lifts the doubleaction hammer sear 25 andthereafter overrides the same thus provoking double-action firing of thepistol, all in manner as is well known. Also in well known manner, themovement of the trigger 16 in the direction of arrow B commensurate witheither the single-action or doubleaction movement of the mechanism 14lifts the hand element 17, which is pivotally mounted on trigger 16 bythe hand axle 29, so that the hand element 17 engages the conventionalcylinder ratchet 30 to commensurately rotate the cylinder 13 to indexone of its cartridge receiving chambers 31 into firing alignment withthe bore 32 of the barrel 12. In either case, the disengagement oroverriding of the trigger sear 24 with respect to either of therespective hammer sears 23 or 25 permits the hammer 15 to spring forwardin response to the bias of main spring 18 so that its hammer pin 15awill strike and fire the cartridge (generally indicated by referencenumeral 33) which is contained in the indexed cartridge receivingchamber 31. Return of the trigger 16 from its firing position to itsreleased position as shown in FIGURES 1 and 2, after the firing of thecartridge 33, is responsive to the downward urging of rebound lever 19on the hand element shoulder portion 17a which urging is, in turn,transmitted to the trigger 16 via the hand axle 29.

As is also conventional, the cylinder stop 20 is pivotally mounted forrocking type movement on a pin 34 attached to the frame 11. The cylinderstop 20 has a forward end 35 which is adapted to successively engage anddisengage the peripherally spaced cylinder detents 36 commensurate witheach chamber indexing rotative movement of the cylinder 13. Its oppositsend 37 is adapted to engage a laterally projecting lug 38 of the reboundlever 19. As previously mentioned, the rebound lever 19 is biased intoengagement at its forward or free end with the hand 17 (through itsshoulder portion 17a) by the urging of the lower leaf 18a of main spring18, the rebound lever 19 being pivotally mounted at its opposite end tothe frame 11 by a pin 39. Thus, the lifting of hand element 17commensurate with the cocking movement of the hammer 15 and trigger 16,as previously described, lifts the rebound lever 19 in the direction ofarrow C. During such pivotal movement of the rebound lever 19, therearward end 37 of the cylinder stop 20 will also be urged upwardly byits engagement of the laterally projecting rebound lever lug 38. Thecylinder stop is thereupon pivoted about the axis of its mounting pin 34so that its forward end 35 moves downwardly out of engagement with oneof the cylinder detents 36, into which the end 35 has previously beenbiased by the upward urging of a cylinder stop spring 40. At its lowerend, the spring 40 is mounted within a recess 41 of the frame 11 at alocation which is laterally adjacent to the trigger 16 and, at its upperend, the spring 40 is in bias pressure engagement with the underside ofthe cylinder stop 20 at a location adjacent the forward end 35 of thelatter. A downwardly projecting pin 42 of the cylinder stop 20 assuresengagement of the spring 40 with the cylinder stop. Upon furthermovement of the rebound lever 19 in the direction of arrow C in responseto continued firing actuation movement of the trigger 16 and hammer 15,the cylinder stop end 37 rides off the rebound lever lug 38, therebypermitting the cylinder stop 20 to pivot in opposite direction,responsive to the urging of its spring 40, so that its forward end 35 isthereupon biased into seating engagement with the cylinder detent 36which is next in sequence around the cylinder 13 upon the chamberindexing movement of the cylinder having been completed. Such engagementof the cylinder stop end 35 within any cylinder detent 36 will limit therotative movement of the cylinder 13 in indexing one of its cartridgereceiving chambers 31 into alignment with the barrel bore 32 of thepistol, as is understood by those having skill in the art. As is alsowell understood, upon the trigger and hammer sear elements becomingdisengaged or riding apart in response to the aforementioned additionalmovement required to fire the pistol, and upon the trigger 16 beingreleased by the finger, the urging of main spring 18 will cause therebound lever 19 to pivot in direction opposite to that shown by arrowC, whereupon the rebound lever lug 38 will drop past the cyinder stopend 37 to position the lug 38 therebelow for initiating another cycle ofrocking movement of the cylinder stop 20 in response to a subsequentfiring actuation of the trigger. For this purpose, the cylinder stop 20is made of thin stock towards its end 37 so that, due to the respectiveconfronting configurations of the cylinder stop end 37 and the side edgeof the rebound lever lug 38, the cylinder stop end 37 will resilientlydeform in lateral direction, with respect to its plane of pivotalmovement, to permit such repositioning of the rebound lever lug 38 withrespect to the cylinder stop end 37 at the end of the firing actuationcycle.

Mounted on the frame 11 by a pivot shaft 47a for swinging movementtowards the opposite side of the pistol as viewed in FIGURE 1, andtherefore illustrated only by dotted line showing in that figure, is aconventional cylinder crane 47, on which the cylinder 13 is mounted,which permits the cylinder 13 to be swung ninety degrees outwardly withrespect to the frame 11, in direction towards the rearward side ofFIGURE 1 or the left hand side of FIGURE 3, for manual loading of thecartridges 33 into the respective cartridge chambers 31.

Turning now to the novel features provided by the present invention,FIGURES 1 and 3 show that the cylinder 13 has six annularly disposedcartridge receiving chambers 31. The cylinder 13 is elongated, ascompared with the cylinder length usually found in conventionalrevolvers, to accommodate up to 3" length cartridges of the shotgun typesuch as those illustrated in FIGURES 6-8, and the bore diameter of eachcartridge receiving chamber 31 is such as to accommodate a .410 gaugecartridge, although the cylinder and chambers may be sized to receivecartridges of larger or smalle gauge or length.

So that the cylinder 13 when in its normal cartridgefiring position asshown in FIGURES 1-3 may be manually rotated to selectively index any ofits six cartridge chambers 31 into the position or indexing stationwhich, in the direction of cylinder indexing movement responsive to afiring actuation of the mechanism 14, is next away from its alignmentwith the barrel bore 32, the cylinder stop 20 has an attached button 43which projects through a substantially vertical slot 44 of the frame 11.As shown in FIGURES 1, 2 and 5, button 43 is attached to the cylinderstop 20 at a location therealong which is a distance away from thepivotal axis 34 of the cylinder stop, preferably in the direction of thecylinder stop forward end 35, although the button might be attachedadjacent the cylinder stop rearward end 37 depending upon whetherdownward or upward movement of the button is preferable at the time whenthe cylinder 13 is to be manually rotated. The buttton shaft 45 isattached to the cylinder stop 20 as by a threaded connection 46, asshown in FIGURE 3. Thus, when it is desired to manually index anyparticular cartridge chamber 31 into the position which is next awayfrom its alignment with the pistol barrel when the cylinder is in itsready position as shown in FIGURES 1 to 3, the finger of one hand isused to depress the button 43 to its lower position, as shown by dottedlines in FIGURE 3, whereupon the cylinder stop forward end 35 is loweredand temporarily retained out of engagement with any cylinder detent 36,the pivotal movement of the cylinder stop 20 being against the bias ofits spring 40. The fingers of the other hand are then employed tomanually rotate the cylinder 13 as desired, after which the button 43 isreleased to again permit the normal engagement of the cylinder stop end35 with one of the cylinder detents 3 As previously mentioned, thepistol 10 may have a different type of firing action mechanism such as,for example, the standard Smith & Wesson double or single action firingmechanism. Although not illustrated, the Smith & Wesson mechanism alsoincludes a spring biased and depressible cylinder stop lever but whichis pivotally and slidably mounted on the gun frame at a location forwardof the trigger so that it is first depressed and then released, during afiring actuation of the mechanism, by a sear on the forward end of thetrigger. A cylinder-stop release button can be attached to the cylinderstop of such mechanism in manner similar to that herein described inconnection with the standard Colt mechanism, although the elongatedframe slot, through which the button will project, may be disposed at anangle to the vertical, rather than vertical, as may be required topermit the normal slidable movement of the cylinder stop in forwarddirection as it disengages a cylinder detent. Such modifications to suitparticular firearms will be apparent to those having skill in the art.

Referring again to FIGURES 1 and 3, because of the upward movement ofthe hand 17 and the consequent chamber indexing movement of the cylinder13 during either single-action or double-action actuation of themechanism 14 when cocking and firing the pistol 10 as previouslydescribed, it will be noted that the chamber 31 containing the cartridgenext desired to be fired should be manually indexed to the station nextaway from its alignment with the barrel so that it will be finallyindexed into barrel alignment commensurate with the next firing actionmovement of the mechanism 14. In this connection, it is seen that thehand element 17 engages the left hand side of the cylinder ratchet asindicated in FIGURE 3, so that the cylinder 13 rotates in clockwisedirection as seen in that figure during a firing actuation movement ofthe mechanism 14. Moreover, the cylinder detents 36 are located on thesurface of cylinder 13 adjacent the respective cartridge chambers 31.Thus, the correct manually indexed position of that cartridge chamberwhich contains the cartridge 33 next to be fired is the position D asindicated in FIG- URE 3. If the cylinder is loaded with cartridgeshaving different types of loads, identification of .the type ofcartridge which has been previously inserted in the cartridge chamberwhich has been manually indexed to position D is facilitated by theplacement of descriptive wording or other indicia 48 on the cylinder 13adjacent the respective cartridge chambers 31. Preferably, the indicia48 is printed on pressure-sensitive adhesive tape or the like tofacilitate its removal and replacement by other indicia, as desired. Itwill be noted that the indicia appears in upright position at positionD, but appears inverted on the opposite side of the pistol 10, whichavoids the possibility of error regarding the type of cartridge next tobe fired.

FIGURES 6 through 8 respectively illustrate only three of the variety oftypes of loads which the cartridges 33 may contain. FIGURE 6 illustratesa cartridge 33a containing a load of bird shot 49 packed in usualmanner, the load of gun powder being indicated by reference numeral 50,and conventional wadding being indicated by reference numeral 51. FIGURE7 illustrates a cartridge 33b having a multiple, large ball load 52.FIGURE 8 shows a cartridge 336 having a rifled slug 53 as the load to befired, its rifling being indicated by numeral 53a. In addition, it iscontemplated that cartridges 33 may be loaded as a flare which, whenfired, will light an otherwise darkened target for about twenty seconds,which is sufiicient time for the position and condition of the target tobe observed prior to selection of another type of load which will nextbe fired. For example, the next cartridge 33 in firing sequence maycontain a load of tear gas, or standard buck shot, as desired.Alternatively, cartridge 33 may contain blank loads for celebration orsport use, or virtually any other conceivable type of load. Aspreviously noted, all six cartridges loaded into the pistol may haveeither the same or a variety of types of loads.

The barrel bore 32 in the pistol of FIGURE 1 has a smooth, parallel-boreportion 32a extending the major portion of its length from its breechend as indicated, the bore diameter being that as is conventional in.410 gauge shotguns, and has a rifled parallel-bore portion 32bextending the remainder of its length towards its muzzle end. Therifling within the rifled portion 32b has conventional standard flutingand pitch. The barrel bore 32 has a boreconstricting choke 32c betweenits smooth bored and rifled portions 32a, 32b. In the embodiment beingdescribed, the overall barrel length is nominally 6"; the length of itsrifled portion is nominally 1 /2"; and the size of its choke 320 is thatof a standard shotgun, i.e. up to about .040". The rifled and chokedportions 32b and 320 of the barrel are further illustrated in FIGURE 4.

Turning now to the preferred embodiments of the barrel, the barrel 55 asshown in FIGURE 9 has three chokes 56, 57 and 58 along its interiorlength, and the barrel 65 as shown in FIGURE 10 has four chokes 66, 67,68 and 69. The sizes of the chokes are deter-mined by the diameterdifferences at the respective junctures of the barrel bore portionsbetween them as indicated, the tandem-arranged barrel bore portions eachbeing parallel-bored, and having sequentially smaller respectivediameters towards the muzzle end of the barrel. As does the barrel 32 ofFIGURE 1, each barrel 55, 65 has standard pistol weight with referenceto wall thickness, etc., and has .410 diameter bore at its breech end,although a larger or smaller bore may be used as aforesaid. Barrels 55,65 are therefore interchangeable with barrel 32. in the pistol 10 ofFIGURE 1. Although each illustrated barrel 55, 65 has nominal overalllength of 10", its multiple choke and rifling features can beincorporated in standard weight barrels having longer length, or shorterlength such as 6" or 8".

The barrel 55 has a smooth, .410" diameter parallelbore portion 59aextending approximately 7%" of its length from its breech end 55a. Theremainder of its length is choked in three stages to .350" diameter atits muzzle end 55b, the total constriction of .060" being equallydivided between the three chokes 56, 57 and 58. Thus, the choking ateach choke 56-58 is .020", the bore portion 59b between chokes 56 and57, and the bore portion 590 between chokes 57 and 58 each being smoothand parallelbored. The bore portion 59d between choke 58 and the muzzleend 55b is parallel-bored and rifled, as at 592, the rifling being ofconventional type. The lengths of the bore portions 59b, 59c and 590!are equal, each being The barrel 65 is parallel and smooth-bored alongeach of its bore portions 70a, 70b, 70c and 70d extending from itsbreech end 65a as shown. Its bore portion 70e between choke 69 and itsmuzzle end 65b is parallel-bored and has standard rifling 701. Althougha total constriction of .060" is achieved over the same length of 2%"and is divided equally between chokes as in the barrel 55, the chokingis in four stages of .015 each. Thus, the diameter of the bore portion70a is .410"; that of portion 70b is .395; that of portion 70c is .380";that of portion 70d is .365"; and that of portion 702 is .350. However,the length of each of the smooth-bored portions 70b, 70c and 70d is /2"whereas the length of the rifled bore portion 702 is With regard to thelength of the rifled bore portion in any of the described barrels, it isbelieved that where a single choke is employed as in the FIGURE 1embodiment the rifled portion 32b should not be greater than about 3",and is preferably less. However, where multiple chokes are employed suchas in the FIGURES 9 and 10 embodiments, the rifled length may beconsiderably shorter, as is advantageous. It is believed that, inaddition to more stable projectile flight due to imparted spin, theshorter rifling at the muzzle end produces a more desirable spread ofbirdshot, buck shot and multiple largeball loads such as four or fiveball loads. For example, it has been discovered that where the length ofthe riflng' is equal to or longer than the total contiguous length of amultiple large ball load, the balls will fail to spread in a desirablemanner. However, where the rifled length is less than the initial lengthof such load, the balls appear to spread in a desirable, controlledpattern. Thus, the length of the rifled bore portion adjacent the muzzleend of a barrel in accordance with the invention is preferably less thantwice the largest barrel bore diameter, such as .750 as compared with.802 in the embodiments of FIGURES 9 and 10, so that even a two-ballload can be accommodated.

It has further been found that, where such multiple large-ball loads(i.e., ball diameter approximates maximum bore diameter) are to befired, at least two and preferably three or four choke stages should beemployed in achieving the total swaging of the balls as they travelthrough the barrel. Moreover, it appears that the length of each of thebarrel portions between the chokes should be such that, for example asillustrated in FIGURE 10, at least two balls 52 of a five ball stringwill be concurrently within such choked length 70b, 70c, 70d, 702 as theload passes through the barrel. In FIGURE 10, the diameter of each ofthe balls 52 is initially .410" and two such balls will therefore beconcurrently within the /2 length of any of the barrel portions 70bdwhen the load is fired. Multiple choking also appears to have theadvantage of narrowing the spread of fine shot.

The choking at the various choke stages may be fairly abrupt, the taperat each illustrated choke 326, 56-58, or 66-69 being about 45.

Thus, a firearm has been described which achieves all of the objects ofthe invention.

What is claimed is:

1. In a pistol, the improvement comprising cartridge chamber meanshaving a length and a diameter for receiving a shotgun-type cartridge,and a pistol barrel having a breech end forward of said cartridgechamber means and a muzzle end, said barrel having a plurality ofaxially concentric parallel-bore portions extending in tandem relationwith each other within the length of said barrel between its said breechand muzzle ends, each said bore portion in the sequence towards saidmuzzl end being substantially immediately adjacent to its preceding boreportion and having a diameter which is smaller than that of itspreceding bore portion whereby a substantially abrupt bore-constrictingchoke is provided therebetween.

2. In a pistol, the improvement according to claim 1 wherein saidplurality of parallel-bore portions comprises a smooth-bore portionextending a major portion of the length of said barrel substantiallyfrom its said breech end towards its said muzzle end, and a rifled-boreportion immediately adjacent to said muzzle end, said rifledbore portionhaving a length which is less than said length of the cartridge chambermeans.

3. In a pistol, the improvement according to claim 2 wherein said lengthof the rifled-bore portion is less than twice the diameter of saidbreech end bore portion.

4. In a pistol, the improvement according to claim 1 wherein saidplurality of parallel-bore portions comprises a breech end bore portion,a bore portion immediately adjacent to said muzzle end, and at least oneintermediate bore portion between said breech end bore portion and saidmuzzle end bore portion, said breech end bore portion and each saidintermediate bore portion being smoothbored.

5. In a pistol, the improvement according to claim 4 wherein each saidintermediate bore portion has a length which is at least equal to thediameter of said breech end bore portion.

6. In a pistol, the improvement according to claim5 wherein said breechend bore portion extends a major portion of the length of said barrel,and which comprises a plurality of said intermediate bore portions, saidmuzzle end bore portion having ritling therein and a length which isless than twice the diameter of said breech end bore portion.

7. In a pistol, the improvement according to claim 6 wherein each ofsaid bore-constricting chokes provides bore constriction substantiallyequal to that of each other.

8. In a pistol, the improvement comprising frame means, a rotatablecylinder mounted on said frame means and having an annularly disposedplurality of individual cartridge receiving chambers and a correspondingplurality of annularly spaced apart cylinder detent means respectivelyassociated with each said chamber, a pistol barrel having a muzzle endand a breech end mounted on said frame means, said barrel having aplurality of axially concentric parallel-bore portions extending intandem relation with and being substantially immediately adjacent toeach other between said breech and muzzle ends, each said bore portiontowards said muzzle end having a diameter which is smaller than that ofits preceding bore portion whereby a substantially abruptboreconstricting choke is provided therebetween, cylinder stop meansmounted on and within said frame means for movement into and out ofengagement with the respective of said cylinder detent means and beingbiased into its said engagement with any of said cylinder detent means,means defining a slot opening through said frame means, and means onsaid cylinder stop means projecting through said slot opening to theexterior of said pistol for manually moving said cylinder stop meansagainst its said bias and out of its said engagement with said cylinderdetent means.

9. In a pistol, the improvement according to claim 8 wherein saidcylinder has indicia thereon at locations associated with the respectiveof said cartridge receiving chambers for distinguishing said chambersone from another.

10. A pistol barrel having a breech end and a muzzle end, and aplurality of axially concentric parallel-bore portions extending intandem relation with and being substantially immediately adjacent toeach other between said breech and muzzle ends, each said bore portionin the sequence towards said muzzle end having a diameter which issmaller than that of its preceding bore portion whereby a substantiallyabrupt bore-constricting choke is provided therebetween, each of saidbore-constricting chokes providing bore constriction substantially equalto that of each other, said plurality of parallel-bore portionscomprising a rifled bore portion immediately adjacent said muzzle endand a plurality of smooth-bore portions extending between said breechend and said rifled bore portion, that of said smooth bore portionswhich is adjacent said breech end having a length which extends themajor length of said barrel and a diameter substantially equal to .410,each said smooth-bore portion between said smooth-bore portion adjacentsaid breech end and said rifled bore portion having a length at leastequal to said diameter of said smooth-bore portion adjacent said breechend, said rifled bore portion having a diameter substantially equal to.350 and a length substantially equal to .750".

11. A pistol barrel according to claim 10 having two said smooth-boreportions between said smooth-bore portion immediately adjacent saidbreech end and said rifled bore portion, the length of each of said twosmooth-bore portions being substantially .750".

12. A pistol barrel according to claim 10 having three said smooth-boreportions between said smooth-bore portion immediately adjacent saidbreech end and said rifled bore portion, the length of each of saidthree smooth-bore portions being substantially .50.

13. A pistol-length gun barrel having a length not longer thansubstantially 10" and having a breech end and a muzzle end, and aplurality of axially concentric parallelbore portions for receiving andconducting a load fired from a shotgun-type cartridge, said boreportions extending in tandem relation with each other within the lengthof said barrel between its said breech and muzzle ends, each said boreportion in the sequence towards said muzzle end being substantiallyimmediately adjacent to its preceding bore portion and having a diameterwhich is smaller than that of its preceding bore portion whereby asubstantially abrupt bore-constricting choke is provided therebetween,said plurality of parallel-bore portions comprising a breech end boreportion having a length which extends a major portion of the length ofsaid barrel, a bore portion immediately adjacent to said muzzle end,said muzzle end bore portion having rifiing therein and a length whichis less than twice the diameter of said breech end bore portion, and atleast one intermediate bore portion between said breech end bore portionand said muzzle end bore portion, said breech end bore portion and eachsaid intermediate bore portion being smooth-bored, and each saidintermediate bore portion having a length which is at least equal to thediameter of said breech end bore portion.

References Cited BENJAMIN A. BORCHELT, Primary Examiner.

